The CATIE Schizophrenia Trial is part of the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) Project. The schizophrenia trial is being conducted to determine the long-term effects and usefulness of antipsychotic medications in persons with schizophrenia. It is designed for people with schizophrenia who may benefit from a medication change. The study involves the newer atypical antipsychotics (olanzapine, quetiapine, risperidone, clozapine, and ziprasidone)and the typical antipsychotics (perphenazine and fluphenazine decanoate). All participants will receive an initial comprehensive medical and psychiatric evaluation and will be closely followed throughout the study. For most participants the study will last up to 18 months. Everyone in the study will be offered an educational program about schizophrenia and family members will be encouraged to participate.